If you subscribe to the Small World Initiative Facebook Group, you’ve probably seen many posts from Chad Coarsey, a bioengineering student at Florida Atlantic University. From Gram stains to agarose gels to extracts fluorescing under UV light, his posts are instructive and analytical, expressing the thrill of discovery-based research. Originally from North Carolina, Chad was drawn to FAU’s tropical climate, where he boasts of going to the beach between classes. Yet, things didn’t go so well at the beginning of college, when he was faced with a drug-resistant nosocomial infection that almost cost him his life. After a year long recovery, he became interested in understanding microbial virulence and the mechanisms of antibiotic resistance. He was determined to help combat the growing number of multi-drug resistant pathogens. In summer 2013, he took a microbiology course taught by Dr. Joseph Caruso and continued to do research with him, studying drug resistance in the human skin microbiota. When Dr. Caruso introduced Small World Initiative to FAU, he was thrilled to join the project. Chad, who has a congenital amputation of his left arm, developed his own aseptic technique allowing him to use only one hand. He feels that the independence he gets from the course has allowed him to become more efficient as a student and scientist, and has taught him patience. “Small World Initiative has sparked innovation in my academic life,” said Chad. In the future, he will be pursuing further research in the M.S. Bioengineering program at FAU, and plans to explore novel antibiotic-producer screening technologies.
Small World Initiative® Blog
Across the map, Small World Initiative students are devising new strategies to screen their soil bacteria for antibiotic activity. The screening process is akin to the discovery of penicillin, in which Alexander Fleming observed a zone of inhibition produced by the Penicillium mold. Yet every SWI student learns that there are many ways we can visualize scientific data. At Iowa State University, the Cyclones (the school mascot) have developed a new protocol called “CLONE ZONE,” which allows them to observe antagonistic-interactions between soil bacteria and the tester strains (safe-relatives of clinically-relevant pathogens) grown under different culture conditions. The students, led by microbiology and plant pathology lecturer Claudia Lemper, grow their isolates in patches and then plug the patch with the end of a sterile Pasteur Pipette. This produces a core infused with the secreted metabolites, analogous to a Kirby Bauer disc, which is subsequently placed on a lawn or patch of the tester strain. The tester strain is then incubated at its optimal temperature or oxygen environment and later screened for inhibition, which would indicate the presence of antibiotic activity. This protocol provides yet another creative way of visualizing zones of inhibition that resembles art, with all the rigor of science.
Samantha Gruenheid’s class of 105 students at McGill University in Montreal, Canada, has no reason to despair. The class is split into lab cubicles of about 12 students each led by a teaching assistant. This fall semester, they collected soil samples from urban and suburban Montreal and cultured a whopping 2,500 bacterial isolates! The students work in pairs to prioritize two isolates for characterization. Recently, they obtained DNA sequences from the 16S ribosomal RNA genes of these isolates and identified various genera of potentially novel antibiotic-producing bacteria, including ones they had never heard of before. Among them were Brevibacillus, Chryseobacterium, and Dyella, a genus of bacteria that was recently discovered in Tokyo, Japan. Their isolates, many of which were isolated using Potato Dextrose Agar medium, were evenly split between Gram-positives and Gram-negatives. Gram-positive bacilli and actinomycete species typically predominate in traditional bacterial isolations, which skews the biodiversity students are able to observe. Their strategy sheds light into the culture conditions and techniques we can use to recover more diverse bacteria in the soil. Dr. Gruenheid joined Small World Initiative this past summer and is a professor of microbiology who studies host-pathogen interactions. “We’re having so much fun, I love the course!” she said, speaking for herself as well as her students.